Abstract

Aims: To produce a phytosociological synthesis of acidophilous beech forests in Slovakia and to assess their main environmental gradients. Location: Slovakia. Methods: Cluster analysis (Beta flexible linkage method and Bray-Curtis distance as a dissimilarity measure)
was used to find the main vegetation types, whereas detrended correspondence analysis and analysis of variance, corrected with the modified permutation test, were applied to determine the major environmental drivers in species composition. In order to perform a more representative selection
of acidophilous beech forests, a preliminary data set of 2261 recent and historical phytosociological relevés with a cover of Fagus sylvatica more than 25% in the tree layer was classified. The final data set consisting of 255 relevés was repeatedly subjected to numerical
classification. Results: Five associations, which matched to alliances Luzulo-Fagion sylvaticae and Fagion sylvaticae from the class Carpino-Fagetea, were accepted. They corresponded to the associations Poo chaixii-Fagetum sylvaticae Šomšák
1979, Calamagrostio arundinaceae-Fagetum sylaticae Sýkora 1971, Luzulo luzuloidis-Fagetum sylvaticae Meusel 1937, Melampyro pratensis-Fagetum sylvaticae Oberdorfer 1957 and Galio odorati-Fagetum sylvaticae Sougnez et Thill 1959 (subassociation festucetosum
drymejae Hübl et Holzner 1977). The principal environmental gradients responsible for floristic variability of the distinguished vegetation units were altitude, Ellenberg indicator values for soil reaction, mean annual precipitation and temperature. Conclusions: Our study provides
the first complex syntaxonomic revision of acidophilous beech forests in Slovakia using unsupervised numerical classification and in accordance with application of ICPN nomenclatural rules. The proposed syntaxonomic scheme contains the associations distributed under similar habitat conditions
throughout the Central Europe, but also the associations reflecting the local floristic and environmental patterns.